Devices, systems, and methods to fixate tissue within the regions of body, such as the pharyngeal conduit

ABSTRACT

Systems and methods incorporate implant structures, and/or implantation devices, and/or surgical implantation techniques, to make possible the treatment of physiologic conditions, such as sleep disordered breathing, with enhanced effectiveness.

RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/718,254, filed Nov. 20, 2003 now U.S. Pat. No. 7,360,542 andentitled “Devices, Systems, and Methods to Fixate Tissue Within theRegions of the Body, Such as the Pharyngeal Conduit,” and acontinuation-in-part of U.S. patent application Ser. No. 10/656,861,filed Sep. 6, 2003 now U.S. Pat. No. 7,188,627 and entitled “MagneticForce Devices, Systems, and Methods for Resisting Tissue Collapse withinthe Pharyngeal Conduit,” both of which claim the benefit of UnitedStates Provisional Patent Application Ser. No. 60/441,639, filed Jan.22, 2003, and entitled “Magnetic Splint Device and Method for theTreatment of Upper Airway Collapse in Obstructive Sleep Apnea,” andUnited States Provisional Patent Application Ser. No. 60/456,164, filedMar. 20, 2003, and entitled “Device and Method for Treatment of SleepRelated Breathing Disorders Including Snoring and Sleep Apnea.” Thisapplication is also a continuation-in-part of co-pending U.S. patentapplication Ser. No. 10/236,455, filed Sep. 6, 2002 now U.S. Pat. No.7,216,648 and entitled “Systems and Methods for Moving and/orRestraining Tissue in the Upper Respiratory System.”

FIELD OF THE INVENTION

The invention is directed to devices, systems, and methods that fixateor brace tissue in targeted body regions, e.g., in the pharyngealconduit for the treatment of sleep disordered breathing includingobstructive sleep apnea.

BACKGROUND OF THE INVENTION

I. The Characteristics of Sleep Apnea

First described in 1965, sleep apnea is a breathing disordercharacterized by brief interruptions (10 seconds or more) of breathingduring sleep. Sleep apnea is a common but serious, potentiallylife-threatening condition, affecting as many as 18 million Americans.

There are two types of sleep apnea: central and obstructive. Centralsleep apnea, which is relatively rare, occurs when the brain fails tosend the -appropriate signal to the breathing muscles to initiaterespirations, e.g., as a result of brain stem injury or damage.Mechanical ventilation is the only treatment available to ensurecontinued breathing.

Obstructive sleep apnea (OSA) is far more common. It is one of theseveral entities that make up the broader group of sleep disorderedbreathing (SDB). This group of disorders ranges from habitual snoring toOSA. Normally, the muscles of the upper part of the throat keep theairway open to permit air flow into the lungs. When the muscles of theupper airway relax and sag, the relaxed. tissues may vibrate as airflows past the tissues during breathing, resulting in snoring. Snoringaffects about half of men and 25 percent of women—most of whom are age50 or older.

In more serious cases, the airway becomes blocked, making breathinglabored and noisy, or even stopping it altogether. In a given night, thenumber of involuntary breathing pauses or “apneic events” can be quitefrequent. These breathing pauses are almost always accompanied bysnoring between apnea episodes, although not everyone who snores hasOSA.

Lack of air intake into the lungs results in lower levels of oxygen andincreased levels of carbon dioxide in the blood. The altered levels ofoxygen and carbon dioxide alert the brain to resume breathing and causearousal. The frequent interruptions of deep, restorative sleep oftenlead to early morning headaches, excessive daytime sleepiness,depression, irritability, and learning and memory difficulties.

The medical community has become aware of the increased incidence ofheart attacks, hypertension and strokes in people with moderate orsevere obstructive sleep apnea. It is estimated that up to 50 percent ofsleep apnea patients have high blood pressure.

Upon an apneic event, the sleeping person is unable to continue normalrespiratory function and the level of oxygen saturation in the blood isreduced. The brain will sense the condition and cause the sleeper tostruggle and gasp for air. Breathing will then resume, often followed bycontinued apneic events. There are potentially damaging effects to theheart and blood vessels due to abrupt compensatory swings in bloodpressure. Upon each event, the sleeping person will be partially arousedfrom sleep, resulting in a greatly reduced quality of sleep andassociated daytime fatigue.

Although some apneic events are normal in all humans, the frequency ofblockages will determine the seriousness of the disease and opportunityfor health damage. When the incidence of blockage is frequent,corrective action should be taken.

II. Sleep and the Anatomy of the Upper Airway

As FIGS. 1A and 1B show, the upper airway consists of a conduit thatbegins at the nasal valve, situated in the tip of the nose, and extendsto the larynx. Although all tissue along this conduit is dynamic andresponsive to the respiratory cycle, only the pharyngeal conduitstructures—the tissues in the region of the airway that starts behindthe nasal cavity and ends in its connections to the supraglotticlarynx—is totally collapsible. The pharyngeal structures and individualanatomic components within this region include the pharyngeal walls; thebase of the tongue; the vallecula; the hyoid bone and its attachments;the soft palate with uvula, the palatine tonsils with associated pillartissue; and the epiglottis.

The cross sectional area of the upper airway varies with the phases ofthe respiratory cycle. At the initiation of inspiration (Phase I), theairway begins to dilate and then to remain relatively constant throughthe remainder of inspiration (Phase II). At the onset of expiration(Phase III) the airway begins to enlarge, reaching maximum diameter andthen diminishing in size so that at the end of expiration (Phase IV), itis at its narrowest, corresponding to the time when the upper airwaydilator muscles are least active, and positive intraluminal pressure islowest. The upper airway, therefore, has the greatest potential forcollapse and closure at end-expiration. Schwab R J, Goldberg A N. UpperAirway Assessment: Radiographic and other Imaging Techniques.Otolaryngol Clin North Am 1998; 31:931-968.

Sleep is characterized by a reduction in upper airway dilator muscleactivity. For the individual with obstructive sleep apnea (OSA) andperhaps the other disorders which comprise much of the group of entitiescalled obstructive sleep-disordered breathing (SDB), it is believed thatthis change in muscle function causes pharyngeal narrowing and collapse.Two possible etiologies for this phenomenon in OSA patients have beentheorized. One is that these individuals reduce the airway dilatormuscle tone more than non-apneics during sleep (the neural theory). Theother is that all individuals experience the same reduction in dilatoractivity in sleep, but that the apneic has a pharynx that isstructurally less stable (the anatomic theory). Both theories may infact be contributors to OSA, but current studies seem to support thatOSA patients have an intrinsically structurally narrowed and morecollapsible pharynx. Isono S. Remmers J, Tanaka A Sho Y, Sato J, NishinoT. Anatomy of Pharynx in Patients with Obstructive Sleep Apnea and inNormal Subjects. J Appl Physiol 1997: 82:1319-1326.

Although anatomic closure is often accentuated at specific sites, suchas the velopharyngeal level [Isono, Ibid], studies of closing pressures[Isono, Ibid] supports dynamic fast MRI imaging that shows narrowing andcollapse usually occurs along the entire length of the pharynx. ShellockF G, Schatz C J, Julien P, Silverman J M, Steinberg F, Foo T K F, Hopp ML, Westbrook P R. Occlusion and Narrowing of the Pharyngeal Airway inObstructive Sleep Apnea: Evaluation by Ultrafast Spoiled GRASS MRImaging. Am J of Roentgenology 1992:158:1019-1024.

III. Prior Treatment Modalities

To date, the only modality that addresses collapse along the entireupper airway is mechanical positive pressure breathing devices, such ascontinuous positive airway pressure (CPAP) machines. All othermodalities, such as various surgical procedures and oral appliances, bytheir nature, address specific sectors of the airway (such as palate,tongue base and hyoid-vallecula levels), but leave portions ofpharyngeal wall untreated. This may account for the considerably highersuccess rate of CPAP over surgery and appliances in controlling OSA.Although CPAP, which in essence acts as an airway splint for therespiratory cycle, is highly successful, it has some very significantshortcomings. It can be cumbersome to wear and travel with, difficult toaccept on a social level, and not tolerated by many (for reasons such asclaustrophobia, facial and nasal mask pressure sores, airwayirritation). These factors have lead to a relatively poor long-termcompliance rate. One study has shown that 65% of patients abandon theirCPAP treatment in 6 months.

The need remains for simple, cost-effective devices, systems, andmethods for reducing or preventing sleep disordered breathing events.

SUMMARY OF THE INVENTION

One aspect of the invention provides systems and methods that includeimplant structures, and/or implantation devices, and/or surgicalimplantation techniques, which make possible the treatment ofphysiologic conditions with enhanced effectiveness.

In one embodiment, then systems and methods provide treatment fordysfunctions affecting the pharyngeal conduit, such as sleep disorderedbreathing, snoring, or sleep apnea. The systems and methods provide animplant that is sized and configured to be implanted in a targetedtissue region comprising at least one pharyngeal structure or at leastone anatomic component within a pharyngeal conduit. The systems andmethods also provide at least one tool and/or instructions for placingthe implant 206 in a tissue region, e.g., through a percutaneous accesspath; or by forming a surgical flap; or by forming a surgical pocket.The systems and methods can also include providing at least one tooland/or instructions for stabilizing the implant within a mucosa, or asubmucosa, or against a fascia, or against or within a muscle; or,alternatively, the tool and/or instructions can make possible thestabilization of the implant against a submucosa, or a fascia, oragainst or within a muscle, without stabilizing through a mucosa. Thesystems and methods can include other tools and instructions, e.g., tomake various mechanical fixation materials for the implant accessible;or to make agents that stimulate rapid fibrosis in the implantation siteavailable; or to provide antibiotic materials for the implantation site.The systems and methods can comprise the components individually or asan assembled kit. The various instructions can be in written form,electronic form, or verbal form, which can be provided in the kit and/oras part of a training program or web site for clinicians.

The systems and methods can be used to treat airway collapse andincreased airway resistance associated with the entire spectrum ofobstructive sleep-disordered breathing. The systems and methods can alsobe used to lend upper airway support in neurological associated dystonicdisorders.

Another aspect of the invention provides a polymer-bonded magneticimplant. The implant comprises a biocompatible polymer matrix sized andconfigured to be implanted in animal tissue. Magnetic particles arebound with the biocompatible polymer matrix. The magnetic particles aremagnetized to possess a desired polarity. The magnetic particles canform regions of different particle densities within the biocompatiblepolymer matrix, or the magnetic particles can comprise an essentiallyuniform particle density within the biocompatible polymer matrix.

In one embodiment, at least one other magnet structure is encapsulatedwithin the biocompatible polymer matrix with the magnetic particles. Theother magnet can comprise a discrete permanent magnet, or apolymer-bonded magnet.

Another aspect of the invention provides a focused magnetic implant. Theimplant comprises a structure sized and configured to be implanted inanimal tissue. The structure including at least one magnet made from ahard ferromagnetic material and a flux shield comprising a softferromagnetic material overlaying at least a portion of the magnet. Theflux shield focuses and enhances the magnetic field of the magnet indirections that the shield does not overlay.

Another aspect of the invention provides a stabilized magnetic implant.The implant comprising a structure sized and configured to be implantedin animal tissue. The structure includes at least one magnet made from ahard ferromagnetic material having a desired magnetic pole. At least onestabilization magnet is provided having a magnetic pole that is the sameas the desired magnetic pole and that is oriented normal or at an acuteangle to the desired magnetic pole. Should rotational misalignment ofthe implant relative to another magnetic implant occur, the presence ofthe stabilizing magnet keeps the magnetic field forces aligned. As aresult, destabilizing magnetic fields are reduced due to misalignment.

Other features and advantages of the invention shall be apparent basedupon the accompanying description, drawings, and claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an anatomic view of the upper airway in a human, showingcertain pharyngeal structures and individual anatomic components withinthe pharyngeal conduit, and the showing the installation of a magneticforce system in the tongue and pharyngeal wall.

FIG. 2 is a superior anatomic view taken generally along line 2-2 inFIG. 1, showing the magnetic force system shown in FIG. 1, which, inuse, fixates or braces tissue in that targeted body region.

FIG. 3 is a perspective front view of a magnetic structure that can beused in the magnetic force system shown in FIG. 2, the structureincluding an array of permanent magnets mounted on a flexible carrier.

FIG. 4 is a perspective front view of an alternative embodiment ofmagnetic structure that can be used in the magnetic force system shownin FIG. 2, the structure including an array of polymer-bonded magnets.

FIG. 5 is a perspective front view of an alternative embodiment ofmagnetic structure that can be used in the magnetic force system shownin FIG. 2, the structure including an array of permanent magnets mountedin a polymer-bonded magnetic array.

FIG. 6 is a perspective front view of an alternative embodiment ofmagnetic structure that can be used in the magnetic force system shownin FIG. 2, the structure including an array of polymer-bonded magnetsincorporated into in a polymer-bonded magnetic array.

FIGS. 7 and 8 are perspective front views of the magnetic structureshown in FIG. 6, showing the inclusion of structures or geometries thatencourage tissue ingrowth to secure the structure within tissue.

FIG. 9 is a perspective front view of an alternative embodiment ofmagnetic structure that can be used in the magnetic force system shownin FIG. 2, the structure including layers of polymer-bonded magnetsincorporated into in a polymer-bonded magnetic array.

FIG. 10 is a perspective front view of an alternative embodiment ofmagnetic structure that can be used in the magnetic force system shownin FIG. 2, the structure including layers of polymer-bonded magnetsincorporated into in a polymer-bonded magnetic array proving a graduatedflux field.

FIG. 11 is a perspective front view of a magnetic structure of the typeshown in FIG. 9 or 10, having magnetic end regions separated by anon-magnetic center, the end regions comprising layers of polymer-bondedmagnets incorporated into in a polymer-bonded magnetic array.

FIG. 12 is perspective front view of the magnetic structure shown inFIG. 11, showing the inclusion of structures that encourage tissueingrowth to secure the structure within tissue.

FIG. 13 is a perspective side views of a shielded magnetic structurecomprising a permanent magnet core enclosed within a soft ferromagneticmaterial, which exposes but a single pole surface to focus the fluxfiled in that direction.

FIGS. 14A, 14B, and 14C show an unshielded permanent magnet core (FIG.14A), its unfocused flux density distribution (FIG. 14B), and thelikewise unfocused bell shaped distribution of the Z component of itsflux density.

FIGS. 15A, 15B, and 15C show a shielded permanent magnet core of thetype shown in FIG. 13 (in FIG. 15A), its focused flux densitydistribution (FIG. 15B), and the likewise focused spike-shapeddistribution of the Z component of its flux density.

FIGS. 16A and 16B are perspective side views of alternative embodimentsof shielded magnetic structures each having a focused flux densitydistribution and a likewise focused spike-shaped distribution of the Zcomponent of its flux density performance characteristics comparable tothat shown in FIGS. 15B and 15C.

FIGS. 17A and 17B show an alternative embodiment of a shielded magneticstructure comprising a permanent magnet core shielded on one polesurface by a soft ferromagnetic material (FIG. 17A) and the focusedspike-shaped variation of the Z component of its flux density (FIG.17B).

FIGS. 18A and 18B are perspective side views, respectively exploded andassembled, of a stabilized magnetic assembly comprising a permanentmagnet core, an attached pair stabilizing permanent magnets, and asingle pole shield of soft ferromagnetic material of a type shown inFIG. 17A.

FIG. 18C is a perspective front view of an alternative embodiment ofstabilized magnetic structure that can be used in the magnetic forcesystem shown in FIG. 2, the structure including an array of stabilizedmagnetic assemblies shown in FIG. 18B mounted on a flexible carrier.

FIGS. 18D(1) and 18D(2) are perspective front views of an alternativeembodiments of stabilized magnetic structures that can be used in themagnetic force system shown in FIG. 2, the structures including an arrayof permanent magnet cores mounted on a flexible carrier, with the poleof at least one of the magnet cores reoriented by ninety degreesrelative to its neighboring cores.

FIG. 18E is a perspective front view of an alternative embodiment ofstabilized magnetic structure that can be used in the magnetic forcesystem shown in FIG. 2, the structure including an array of stabilizedmagnetic assemblies shown in FIG. 18B mounted in two rows on a flexiblecarrier.

FIGS. 19A, 19B, 19C, and 19D are perspective anatomic views of a tongueand adjacent pharyngeal wall, simplified and diagrammatic, showing theformation of a surgical flap on a lateral pharyngeal wall and theimplantation of an implant in the flap.

FIGS. 20A, 20B, 20C, and 20D are perspective anatomic views of apharyngeal wall, simplified and diagrammatic, showing the formation of asurgical flap on a posterior-lateral pharyngeal wall and theimplantation of an implant in the flap.

FIGS. 21A, 21B, 21C, and 21D are anatomic views of a tongue within anoral cavity, simplified and diagrammatic, showing the formation of asurgical flap on the posterior tongue and the implantation of an implantin the flap.

FIG. 22 is a perspective view of an implant system comprising a sleeveinto which an implant can be inserted.

FIGS. 23A, 23B, and 23C are perspective anatomic views of a tongue andadjacent pharyngeal wall, simplified and diagrammatic, showing theformation of a surgical flap on a lateral pharyngeal wall and theimplantation of the implant system shown in FIG. 22 in the flap.

FIGS. 24A, 24B, and 24C show an instrument system for percutaneouslyimplanting an implant comprising a cylindrical access cannula throughwhich a correspondingly-shaped tissue dissection tool and implantdelivery tool can be passed, FIG. 24A showing passage of the tissuedissection tool through the cannula, FIG. 24B showing the passage of theimplant delivery tool through the cannula, and FIG. 24C showing thedelivery of the implant by the implant delivery tool.

FIGS. 25A, 25B, and 25C show an instrument system for percutaneouslyimplanting an implant comprising a rectilinear access cannula throughwhich a correspondingly-shaped tissue dissection tool and implantdelivery tool can be passed, FIG. 25A showing passage of the tissuedissection tool through the cannula, FIG. 25B showing the passage of theimplant delivery tool through the cannula, and FIG. 25C showing thedelivery of the implant by the implant delivery tool.

FIG. 26A is perspective anatomic view of a tongue and adjacentpharyngeal wall, simplified and diagrammatic, showing the use of theinstrument system shown in FIGS. 24A to 24C to place an implant in aposterior tongue.

FIG. 26B is perspective anatomic view of a tongue and adjacentpharyngeal wall, simplified and diagrammatic, showing the use of theinstrument system shown in FIGS. 25A to 25C to place an implant in alateral pharyngeal wall.

FIGS. 27A and 27B are perspective side views of an alternativeembodiment of an instrument system for percutaneously implanting animplant, the system including a syringe-like remote actuator to expel animplant from a needle-cannula carried at the distal end of a flexibletube.

FIGS. 28A and 28B are perspective side views of an alternativeembodiment of an instrument system for percutaneously implanting animplant, the system including a trigger-like remote actuator to expel animplant from a needle-cannula carried at the distal end of a flexibletube.

FIGS. 29A and 29B are perspective side views of an alternativeembodiment of an instrument system for percutaneously implanting animplant, the system including a sliding remote actuator to expel animplant from a needle-cannula carried at the distal end of a flexibletube.

FIGS. 30A, 30B, 30C, and 30D are perspective views of an implant andassociated delivery tool, the implant having integrated tissuestabilization elements, which are automatically deployed into tissue asthe implant is expelled from the delivery tool, FIG. 30A showing theoutboard configuration of the implant stabilization elements after theimplant has been completely expelled from the tool, FIGS. 30B and 30Cshowing the loading of the implant into the tool, during which thestabilization elements are bent toward a low profile inboardconfiguration, and FIG. 30D showing the deployment of the stabilizationelements as the implant is being expelled from the tool.

FIG. 31 is a perspective view of an integrated system in kit form thatincludes an implant component and an implantation component, which makepossible the treatment of physiologic conditions, e.g., dysfunctionsaffecting the pharyngeal conduit, such as sleep disordered breathing,snoring, or sleep apnea.

DETAILED DESCRIPTION

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention, which may be embodiedin other specific structure. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention, which is defined by the claims.

I. Magnetic Force Systems to Fixate or Brace Tissue

A. Overview

FIGS. 1 and 2 show a magnetic force system 10 that, in use, fixates orbraces tissue in a targeted body region. In FIGS. 1 and 2, the targetedbody region comprises pharyngeal structures and individual anatomiccomponents within the pharyngeal conduit. The targeted pharyngealstructures and individual anatomic components within this region caninclude the pharyngeal walls; the base of the tongue; the vallecula; thesoft palate with uvula; the palatine tonsils with associated pillartissue; and the epiglottis. These anatomic regions are shown in FIG. 1.

In the particular embodiment illustrated (see FIG. 2), the magnet forcesystem 10 includes one or more ferromagnetic structures 12 implanted inthe pharyngeal wall and/or one or more ferromagnetic structures 14implanted in the posterior of the tongue. Both ferromagnetic structures12 and 14 comprise at least one permanent magnet. Examples of knownpermanent magnet materials include alloys of Neodymium-Iron-Boron(NdFeB), alloys of Aluminum-Nickel-Cobalt (AlNiCo), and Samarium Cobalt(SmCo). The permanent magnets can be magnetized through the thickness ina variety of modes, such as multipole faces, radial homopolar, axial, ordiametrical.

The permanent magnets in the opposing structures 12 and 14 possess thesame magnetic orientation (North-North or South-South). According tophysical laws, poles of like polarity repel each other with a magneticforce. The force of magnetic repulsion depends on the strength of themagnets and the distance between the poles.

The repelling force between the opposing tongue magnet(s) and pharyngealwall magnet(s) is selected to be of a strength sufficient to remodelnative tissue conditions within the airway. The repelling force altersexisting morphology and/or motility and/or shape of tissue that, if notaltered, could lead to tissue collapse, particularly during therespiratory cycle. The implanted ferromagnetic structures 12 and 14establish tissue conditions that fixate or brace the tissue, to resistcollapse along the pharyngeal conduit when imminent, i.e., during sleep,but without significantly stiffening the native tissue at times whentissue collapse is not imminent.

The orientation of the structures 12 and 14 can vary. The structures 12and 14 may be oriented within tissue horizontally (as shown in FIG. 2),and/or vertically (see, e.g., FIGS. 23C and 26B), and/or diagonally,and/or in intermediate orientations (e.g., sloped), and/or combinationsthereof.

It should be appreciated that one of the structures 12 and 14 can belocated external of the pharyngeal conduit, to magnetically interactwith a structure implanted within the pharyngeal conduit. The magneticforce field created may be attracting and/or repelling, depending uponthe anatomic orientation of the structures and the physiologic outcomedesired. Various embodiments of magnetic force systems using implantedand/or external magnetic structures are shown in U.S. patent applicationSer. No. 10/656,861, filed Sep. 6, 2003 and entitled “Magnetic ForceDevices, Systems, and Methods for Resisting Tissue Collapse within thePharyngeal Conduit,” which is incorporated hereby by reference.

The system 10 can be used to treat airway collapse and increased airwayresistance associated with the entire spectrum of obstructivesleep-disordered breathing. The system 10 can also be used to lend upperairway support in neurological associated dystonic disorders. The system10 can also be used in other regions of the body where tissue remodelingand/or bracing is indicated.

The fixation or bracing function of the implanted structures 12 and 14impart improved comfort, tolerance, and bio-acceptance to the implantedstructures 12 and 14 for the patient. The fixation or bracing functionis achieved without indiscriminate dampening (i.e., stiffening) thespring constant of native tissue in the pharyngeal conduit (which is notdesirable). The fixation or bracing function is achieved due to thecontrolled application of static and/or kinetic forces that push or pullon tissue, without themselves imparting stiffness to the tissue in thepharyngeal conduit. The size and configuration of the implantedstructures are selected with the ease and bio-comfort of implantation inmind, while at the same time providing sufficient static and/or kineticforces to resist tissue collapse when collapse is imminent, taking intoaccount the anatomy of the region of implantation and orientation ofother components of the system 10. The implanted structures 12 and 14thereby provide conformability, tolerance, and comfort for the patient,without significantly dampening the spring constant of native tissue.

B. Magnetic Arrays

The implanted ferromagnetic structures 12 and/or 14 can each comprise asingle or discrete source of magnetism having a given desiredorientation. For example, a single permanent magnet, comprising a bodyof a ferromagnetic material, can comprise a single source of magnetismhaving a given orientation.

A given implanted ferromagnetic structure 12/14 of whatever form orconfiguration can be coated, plated, encapsulated, or deposited with aselected protective material 68 (see FIG. 2). The protective material 68is selected to provide a corrosion resistant and biocompatibleinterface, to prevent interaction between the structure andtissues/fluids of the body. The protective material 68 is also desirablyselected to form a durable tissue interface, to provide longevity to thestructure, and thereby provide resistance to structural fatigue and/orfailure. The protective material 68 can be selected among various typesof materials known to provide the desired biocompatibility, resistanceto corrosion, and durability. For example, the protective material 68can comprise gold,, and/or silver, and/or titanium material plated,deposited, or otherwise coated upon the structure. As another example,the protective material 62 can comprise a parylene coating. As otherexamples, the protective material 68 can comprise a silicone polymer, anon-toxic epoxy, a medical grade polyurethane, or a U.V. curable medicalacrylic co-polymer.

The protective material 68 may also incorporate anticoagulants and/orantibiotics, be antimicrobial in nature, or be treated to create anantimicrobial surface.

-   -   1. Discrete Permanent Magnets on a Flexible Carrier

As shown in FIG. 3, the ferromagnetic structures 12 and/or 14 can eachcomprise a flexible or compliant array of discrete permanent magnets 16,carried as a unit on a support carrier 18, or otherwise directly linkedtogether. The support carrier 18 is desirably made from a material thatimparts biocompatibility, durability, and flexibility to the magneticarray. The carrier 40 may be made, e.g., of a flexible or semi-rigidmaterial such as polycarbonate, silicone rubber, polyurethane, hydrogel,etc, or a flexible or semi-rigid plastic and/or metal and/or fabricand/or textile and/or ceramic material.

The material of the carrier 18 can enclose the magnets 16, or themagnets 16 can be carried on the surface of the carrier 18. The spacingbetween the magnets 16 on or within the carrier 18 provides therequisite flexibility desired. The individual magnets 16 can havevarious geometries—rectangular, cylindrical, spherical, oval, etc.—aslong as the desired physiologic response is achieved.

Further details of flexible magnetic arrays of the type described can befound in copending U.S. patent application Ser. No. 10/236,455, filedSep. 6, 2002 and entitled “Systems and Methods for Moving and/orRestraining Tissue in the Upper Respiratory System,” which isincorporated herein by reference.

-   -   2. Polymer-Bonded Magnetic Structures

The magnetic structures 12 and/or 14 can include one or morepolymer-bonded magnets 20, as shown in FIG. 4. The polymer-bonded magnet20 comprises magnetic particles 22 bound within a biocompatible polymer24. The magnetic particles 22 can comprise either isotropic oranisotropic materials, e.g., NdFeB, SmCo, ferrite and/or alnicoparticles. The biocompatible polymer 24 can comprise, e.g.,polycarbonate, silicone rubber, polyurethane,. silicon elastomer, or aflexible or semi-rigid plastic. Fabric and/or textile and/or ceramicmaterial can also be incorporated within the polymer matrix.

To form the polymer-bonded magnet 20, the magnetic particles 22 arecompounded with the biocompatible polymer 24 in a desired proportion.The proportion of polymer 24 and magnetic particles 22 in the magnet 20can be tailored to provide a desired degree of flexibility, elasticity,and magnetic strength.

The biocompatible polymer 24 is mixed with magnetic particles 22 in apredetermined ratio, and the mixture is compounded (i.e., kneaded).After compounding, the mixture can be molded into a desired shape. Themolding methods can include, e.g., injection molding, compressionmolding, extrusion, and calendering.

Following molding, the molded component can be cut or machined asneeded. Secondary surface coating using other biocompatible polymers maybe applied, if desired. Alternatively, or in combination, two-stagemolding may be accomplished, during which the molded component isover-molded with a layer of biocompatible polymer.

The finished component is then magnetized to possess the desiredpolarity. The polymer-bonded magnet 20 is thereby formed as a singlepiece, which reduces flux leakage.

In the system 10 shown in FIG. 2, the structures 12 and/or 14 could eachinclude a polymer-bonded magnet 20. When positioned in the system 10shown in FIG. 2, the polymer-bonded magnets 20 implanted in thepharyngeal wall and the tongue would possess like polarity, therebycreating the desired repelling force between them.

Finite element analysis shows that two repelling polymer-bonded magnets20, each formed as a strip measuring 4 mm×10 mm×40 mm, are capable ofcreating a maximum energy product of about 0.8 MGOe. Finite elementanalysis based upon this energy product shows that the twopolymer-bonded magnets 20 can generate a repelling force of more than 22grams/cm² when they are positioned 12 mm apart. The magnetic propertiesof the strips and their dimensions can, of course, be changed to fit theapplications.

The shape of a given polymer-bonded magnet 20 can be selected to bestconfirm to the anatomic site of implantation. It is believed that thebiocompatibility, softness, and flexibility of a polymer-bonded magnet20 make it tolerable during chronic implantation in tissue. Larger sizesof a given magnetic structure could also be considered, compared to useof conventional permanent magnets, because the similar mechanicalproperties of the polymer-bonded magnet 20 and the surrounding tissue.

The polymer-bonded magnet 20 can include through holes, and/ornon-through holes, and/or complex surface configurations, and/or othersurface textures, or combinations thereof, to promote tissue in-growthand implant stability. Further discussion of tissue ingrowth surfacesand materials follows.

-   -   3. Hybrid Magnetic Structures

The magnetic structures 12 and/or 14 may include a hybrid magneticstructure 26, as shown in FIG. 5. The hybrid magnetic structure 26 shownin FIG. 5 comprises one or more discrete permanent magnets 28encapsulated within a polymer-bonded magnetic matrix 30. As describedabove, the matrix 30 comprises magnetic particles 22 bound within abiocompatible polymer 24.

The permanent magnets 28 can comprise sintered, high energy, permanentmagnets such as N45 or N48, i.e., possessing a maximum energy product ofabout 45-48 MGOe. If desired (as shown in FIG. 5), one or more threads34 could connect the magnets 28 within the matrix 30, to improvestability of the structure 32.

As previously described, the magnetic particles 22 can comprise eitherisotropic or anisotropic materials, e.g., NdFeB, SmCo, ferrite and/oralnico particles. The biocompatible polymer 24 can comprise, e.g.,polycarbonate, silicone rubber, polyurethane, silicon elastomer, or aflexible or semi-rigid plastic. Fabric and/or textile and/or ceramicmaterial can also be incorporated within the polymer matrix. Within thestructure 26, the permanent magnets 28 and the magnetic particles 22 aremagnetized in the same flux direction.

The hybrid structure 26 takes advantage of the high magnetic strength ofthe sintered permanent magnets 28, and combines this benefit with theflexibility and biocompatibility of a polymer-bonded magnetic matrix 30.Furthermore, the presence of the permanent magnetic particles 22 betweenthe high energy permanent magnets 28 pushes the flux lines emanatingfrom the permanent magnets 28 farther away from the surface of thestructure 26, as compared to permanent magnets 28 in a pure(non-magnetic) polymer matrix. This change in the flux lines reducesflux leakage.

FIG. 6 shows an alternative embodiment of a hybrid magnetic structure32. The structure 32 comprises one or more polymer-bonded magnets 20 (asshown in FIG. 4) encapsulated within a polymer-bonded magnetic matrix30, as just described. The matrix 30 and the polymer-bonded magnets 20each comprises magnetic particles 22 bound within a biocompatiblepolymer 24.

The density of magnetic particles 22 in the magnets 20 is desirablygreater than the density of magnetic particles 22 in the matrix 30. Thisimparts more flexibility to the low-density matrix 30 and highermagnetic force to the higher density magnets 20. If desired (as shown inFIG. 6), one or more threads 34 could connect the higher densitypolymer-bonded magnets 20 within the matrix 30 to improve stability ofthe structure 32.

As previously described, the magnetic particles 22 can comprise eitherisotropic or anisotropic materials, e.g., NdFeB, SmCo, ferrite and/oralnico particles; and the biocompatible polymer 24 can comprise, e.g.,polycarbonate, silicone rubber, polyurethane, silicon elastomer, or aflexible or semi-rigid plastic. Fabric and/or textile and/or ceramicmaterial can also be incorporated within the polymer matrix. Within thestructure 32, the magnetic particles 22 in the magnets 20 and in thematrix 30 are magnetized in the same flux direction.

The hybrid structure 32 takes advantage of the high density, highperformance polymer-bonded magnets 20, and combines this benefit withthe flexibility of the low-density polymer-bonded magnetic matrix 30.Furthermore, as described in connection with the hybrid structure 32 inFIG. 5, the presence of the permanent magnetic particles 22 between thehigh performance polymer-bonded magnets 20 pushes the flux linesemanating from the polymer-bonded magnets 20 farther away from thesurface of the structure 32, as compared to polymer-bonded magnets 20 ina pure (non-magnetic) polymer matrix. This change in the flux linesreduces flux leakage.

In the system 10 shown in FIG. 2, the structures 12 and/or 14 could eachcomprise one of the hybrid magnetic structure 26 and/or 32. Thestructures 26 and/or 32 implanted in the pharyngeal wall and the tonguewould possess like polarity, thereby creating the desired repellingforce between them.

The shape of a given hybrid magnetic structure 26 or 32 can be selectedto best confirm to the anatomic site of implantation. Furthermore,either hybrid magnetic structure 26 or 32 can include through holes 36(see FIG. 7), and/or non-through holes, and/or complex surfaceconfigurations 38 (see FIG. 8), and/or other surface textures, orcombinations thereof, to promote tissue in-growth and implant stability.

-   -   4. Layered Magnetic Structures

The magnetic structures 12 and/or 14 could include a layered magneticstructure 40, as shown in FIG. 9. The layered structure 40 comprises twoor more layers of magnet particles 22 encapsulated in differentdensities within a biocompatible polymer 24. In FIG. 9, six layers L1 toL6 are shown for purposes of illustration, and it should be appreciatedthe number of layers can be greater than or less than six.

The density of magnetic particles 22 in layers L1, L3, and L5 is greaterthan the density of magnetic particles 22 in the neighboring layers L2,L4, and L6. The presence of the less dense layers L2, L4, and L6 impartsoverall flexibility to structure 40, whereas the presence of the moredense layers L1, L3, and L5 imparts higher magnetic force. Thejuxtaposition of the less dense layers L2, L4, and L6 between the moredense layers L1, L3, and L5 pushes the flux lines emanating from thehigher density layers L1, L3, and L5 farther away from the surface ofthe structure 40, as compared to uniform density polymer-bonded magneticlayers. This change in the flux lines reduces flux leakage.

As previously described, the magnetic particles 22 can comprise eitherisotropic or anisotropic materials, e.g., NdFeB, SmCo, ferrite and/oralnico particles; and the biocompatible polymer 24 can comprise, e.g.,polycarbonate, silicone rubber, polyurethane, silicon elastomer, or aflexible or semi-rigid plastic. Fabric and/or textile and/or ceramicmaterial can also be incorporated within the polymer matrix. Within thestructure 40, the magnetic particles 22 in the layers L1 to L6 aremagnetized in the same flux direction.

In FIG. 9, the density of magnetic particles 22 in the higher densitylayers L1, L3, and L5 is shown to be generally the same. In analternative arrangement (see FIG. 10), the density of magnetic particles22 in the higher density layers L1, L3, and L5 can gradually increase.This provides a change in the flux density across the surface of thestructure 40.

In the system 10 shown in FIG. 2, the structures 12 and/or 14 could eachcomprise a layered magnetic structure 40, or a layered magneticstructure 40 used in combination with another type of magneticstructure, such as a flexible array of discrete permanent magnets,polymer-bonded magnets, or hybrid magnetic structures 26 and/or 32.Regardless, the structures 12 and 14 implanted in the pharyngeal walland the tongue would possess like polarity, thereby creating the desiredrepelling force between them.

The shape of a layered magnetic structure 40 can be selected to bestconfirm to the anatomic site of implantation. For example, as shown inFIG. 11, the layered structure 40 can comprise end portions 44 separatedby a connecting strip 46. Each end portion 44 includes the layers L1 toL6 of magnetic particles 22 encapsulated in different densities within abiocompatible polymer 24, as previously described. Alternatively, thelayers L1 to L6 could provide a variation of densities, or the densityof magnetic particle 22 within one or both end portions 44 could beuniform. The connecting strip 46 comprises the biocompatible polymer 24free of magnetic particles 22. The magnetic particles 22 in the endportions 44 are magnetized to have the same polarity, so that the endportions repel each other. The intermediate strip 44, being free ofmagnetic particles 22, does not interfere with the repelling force.

As FIG. 12 shows, the structure 40 can include surface texturing (shownas a pattern of non-through holes H), to promote tissue in-growth andimplant stability. Through holes (as shown in FIG. 7), and/or complexsurface configurations (as shown in FIG. 8), and/or other surfacetextures, or combinations thereof, can be used for the same purpose.

C. Focusing the Magnetic Flux of Magnetic Structures

Regardless of the type of magnetic structure that is implanted, it isdesirable to achieve high repelling forces using an array of magnets ofrelatively small size, which can be tolerated by the body withoutdiscomfort. A way to achieve this objective is to include means forfocusing the magnetic flux in a desired direction, while also reducingthe flux in other directions. The focusing of magnetic flux can makepossible the use of smaller magnets. The focusing of magnetic flux canalso impart stability to the implanted structure, to resist migrationwithin tissue.

FIG. 13 shows a magnetic structure 46 comprising a magnetic core 48 andan overlaying flux shield 50 that includes a soft ferromagneticmaterial. The magnetic core 48 can comprise a rare earth permanentmagnet, or a polymer-bonded magnet, or a hybrid magnetic structure, or alayered magnetic structure, all having previously been described. Thesoft ferromagnetic material of the flux shield 50 has very highpermeability and saturation magnetization, but very low intrinsiccoercivity. Examples of known soft ferromagnetic materials include Iron(Fe); Nickel (Ni); Permendur; MuMetal, low-carbon steels, Iron-Cobaltalloys (Fe—Co); silicon steels; and amorphous alloys.

As the following examples demonstrate, the presence of a flux shield 50of a soft ferromagnetic material focuses and enhances the magnetic fieldof the core 48 in directions that the shield 50 does not overlay. InFIG. 13, the flux shield 50 overlays all but one pole of the core 48.However, as will be shown later, the flux shield 50 need overlay onlyone pole surface of the core 48 to achieve a flux focusing effect.

EXAMPLE 1 Unshielded Core

FIG. 14A shows a core 48 comprising a permanent magnet measuring 40mm×40 mm×25 mm (i.e., a volume of 40,000 mm³ ). FIG. 14B shows the totalflux density distribution on the YZ plane, based upon finite elementmodeling, of the magnetic field generated by the permanent magnet. FIG.14B shows the magnetic field emanating in all directions in the YZ planeabout the magnet. FIG. 14C shows the magnitude of the Z component offlux density (Bz) taken at increasing distances from the top magnetsurface along its center line. FIG. 14C generally shows a bell shapedcurve, with a maximum Bz(T) of 0.6 at a distance of about 62 mm from themagnet surface, with gradual increases with decreasing distances andgradual decreases with increasing distances.

EXAMPLE 2 Shielded Core

FIG. 15A shows a core 48 comprising a permanent magnet smaller than themagnet of Example 1, measuring 30 mm×30 mm×20 mm (i.e., having a lesservolume of 18,000 mm³ ). The magnet has been placed within a flux shield50. The flux shield comprises a box made from a soft ferromagneticmaterial. The box covers all but one pole surface of the permanentmagnet.

FIG. 15B shows the total flux density distribution on the YZ plane,based upon finite element modeling, of the magnetic field generated bythe permanent magnet when housed within the box. FIG. 15B shows that thepresence of the ferromagnetic material of the box significantly altersthe distribution pattern of the flux density of the field on the YZplane. The magnetic field is demonstrably focused in the direction ofthe field that is not shielded by the ferromagnetic material. FIG. 15Cshows the magnitude of the Z component of flux density (Bz) taken atincreasing distances from the unshielded pole surface along its centerline. FIG. 15C confirms the focused nature of the magnetic field. FIG.15C also shows an increase in the flux density of the Z component inExample 2, despite the use of a magnet of significantly lesser volumethan in Example 1. Unlike the curve in FIG. 14C, the curve in FIG. 15Cis not bell shaped. The Z component of the flux density BZ suddenlyspikes at a maximum Bz(T) of 1.2 at a distance of about 55 mm from theunshielded pole, and thereafter maintains a magnitude above 0.6Bz(T)—i.e., above the maximum flux density of the Z component of Example1—at increasing distances up to about 75 mm from the single unshieldedpole of the magnet.

A comparison of FIGS. 14B/C with FIGS. 15B/C demonstrates the ability ofa soft ferromagnetic material to shield and to focus the magnetic fieldemanating from a permanent magnet.

EXAMPLE 3 Alternative Shielded Magnets

FIGS. 16A and 16B show alternative embodiments of magnetic cores 48comprising permanent magnets with flux shields 50 of soft ferromagneticmaterials. Finite element analysis of these alternative embodiments showthe focused flux density distribution shown in FIG. 15B, as well as thespike-curve configuration, shown in FIG. 15C, of the Z component of fluxdensity (Bz) taken at increasing distances from the unshielded magnetpole along its center line.

EXAMPLE 4 Single Pole Shield

FIG. 17A shows magnetic core 48 comprising a permanent magnet havinggenerally the same measurements as the magnet in Example 1. In thisembodiment, the flux shield 50 overlays only one pole of the magnet.FIG. 17B shows that the magnitude of the Z component of flux density(Bz) taken at increasing distances from the unshielded magnet pole alongits center line has been altered by the presence of the single pole fluxshield 50. FIG. 17B shows the same spike-curve configuration shown FIG.15C, demonstrating that the presence of the single pole flux shield 50has focused the magnetic field in the direction of the unshielded magnetpole. FIG. 17B also demonstrates that the maximum strength of themagnetic field has likewise been increased, from 0.6 Bz(T) in Example 1to 0.7 Bz(T) in Example 4: FIG. 17B demonstrates the ability of singlepole flux shield 50 of soft ferromagnetic material to shield and focusthe magnetic field emanating from a permanent magnet.

D. Reducing Instability of the Magnetic Structures

Regardless of the type of magnetic structure that is implanted, it isalso desirable to minimize the effects of instability due to magneticfield forces. It is also desirable to minimize migration or twistingshould misalignment between the magnetic field forces of opposedmagnetic structures 12 and 14 occur. If repelling like poles becomemisaligned, unlike poles may seek to attract and align.

A way to minimize the effects of instability is to include stabilizationmagnets having repelling poles normal or at an acute angle to the majorrepelling pole. By way of illustration, FIGS. 18A and 18B show astabilized magnetic structure 52 comprising a magnetic core 54 joined toa pair of stabilizing magnets 56.

The magnetic core 54 can comprise a rare earth permanent magnet, or apolymer-bonded magnet, or a hybrid magnetic structure, or a layeredmagnetic structure, all having previously been described. The magneticcore 54 has a repelling pole 58 that is sized and configured to beprimarily responsible for the repelling force needed for a givenstructure.

Each stabilizing magnet 56 is secured to a side of the repellingmagnetic core 54, e.g., by adhesive, welding, molding, crimping, orsoldering. The stabilizing magnets 56 comprise rare earth permanentmagnets, or a polymer-bonded magnet, or a hybrid magnetic structure, ora layered magnetic structure, all having previously been described. Thestabilizing magnets 56 each has a repelling pole 60 (i.e., having thesame polarity as the repelling pole 58). The surfaces of the repellingpoles 60 of the stabilizing magnets 56 are oriented at right angles tothe repelling pole 58 of the magnetic core 52. The poles 60 of thepermanent stabilizing magnets 56, like the repelling pole 58 of themagnetic core 52, are all like the poles of the magnet(s) on theopposing magnetic structure.

Should rotational misalignment of one magnetic structure occur, theoutward facing poles 60 of the permanent stabilizing magnets 56 will, toa greater or lesser degree, continue to face the like poles of themagnet(s) on the other magnetic structure. Since the outward facingpoles 60 of the permanent stabilizing magnets 56 are like the poles ofthe other structure, the repelling nature of magnetic field between thetwo structures remains the same—the two magnet structures 12 and 14continue to repel each other. Rotational misalignment may lead to adiminution of the magnetic force field, but the magnetic force field isitself still a repelling field. Destabilizing magnetic fields arereduced due to misalignment, to reduce twisting or otherwisedestabilizing either structure 12/14.

As further shown in FIGS. 18A and 18B, the stabilized magnetic structure52 may includes a shielding pole piece 62 made of a soft ferromagneticmaterial secured to the opposite pole face of the magnetic core 54. Theshielding pole piece 62 serves to alter the distribution and themagnitude of the Z component of flux density (Bz), in the mannerpreviously demonstrated, providing the spike-shaped performancecharacteristic shown in FIG. 17B. The shielding pole piece 62 focusesthe magnetic flux in the desired direction.

In a representative embodiment, the repelling magnetic core 54 has adimension of 2 mm×2 mm×4 mm. Each stabilizing magnet 56 has a dimensionof 1 mm×2 mm ×4 mm. The shielding pole piece 62 has a dimension of 4mm×4 mm×0.5 mm. The resulting structures 52 can be assembled into arrays64 of stabilized magnetic structures 52 (see FIG. 18C). On each array64, the stabilized magnet structures 52 are spaced apart by about 1 mm.Arranged in a facing, repelling relationship at a distance of about 12mm, finite element analysis shows that a repelling force between thearrays 64 can be generated, which can be increased or decreased bychanging the dimensions of the stabilized magnetic structures 52 or thearrays 64. The presence of the shielding pole piece 62 focuses andincreases the flux density in the desired direction between arrays 64.The presence of the stabilizing magnets 56 provides positionalstability, to which the shielding pole piece 62 also contributes byreducing flux density in undesired directions.

As FIG. 18E shows, should the array 64 include more than one row ofadjacent magnetic structures 52 with stabilizing magnets 56, thesurfaces of the magnetic structures 52 that face inward within the array64 need not carry stabilizing magnets 56. In this arrangement, thestabilizing magnets 56 are located along the outside edges of themultiple row array 64.

Positional stability of a given array of magnets can also be enhancedwithout use of stabilizing magnets 56. As shown in FIGS. 18D(1) and18D(2), and as previously described, magnetic cores 54 (comprising e.g.,rare earth permanent magnets, or polymer-bonded magnets, or hybridmagnetic structures, or layered magnetic structures) can be arrangedalong a flexible carrier C. Each magnetic core 54 has a repelling pole58 that is sized and configured for the repelling force needed for agiven structure. Enhanced positional stability in such an array can beachieved by reorienting a repelling pole 58 of one of the magnetic cores54 by ninety-degrees, in either direction (shown, respectively, in FIGS.18D(1) and 18D(2) relative to the orientation of its neighboring cores54. Within a given array, one or more cores 54 can be reoriented in thismanner in either a random or repeating pattern. Should rotationalmisalignment of one magnetic array relative to another magnetic arrayoccur, the presence of at least one reoriented core within one or bothof the arrays will, to a greater or lesser degree, maintain therepelling nature of magnetic field between the two structures.Destabilizing magnetic fields are reduced due to misalignment, to reducetwisting or otherwise destabilizing either array.

II. Fixation of Structures Implanted in Tissue

Implants of the types described herein, or of other designs andfunctions, can be fixed percutaneously into the pharyngeal wall and/ortongue (the locations shown in FIG. 2), and/or elsewhere in thepharyngeal conduit, and/or elsewhere in the body in various ways. Itshould be appreciated that, while the description of various fixationtechniques that follows shows the implant to be a magnetic structure,and the implantation site being in the pharyngeal conduit, suchdescription is for the purpose of illustrating the features and benefitsof a given technique. The features and benefits that will be describedare broadly applicable to any implant placed within an implantation siteanywhere within the body.

A. Use of Mechanical Fixation Materials

The position of implanted magnetic structures 12/14 or any implant ingeneral can be fixed against migration in a targeted tissue region,e.g., within the pharyngeal conduit, using conventional mechanicalfixation materials and techniques known in the surgical arts, e.g.,resorbable or non-resorbable sutures, screws, staples, darts, clips,adhesives, or glues such as cyanoacrylate, or cements such as polymethylmethacrylate (PMMA) cement. For example, the structures 12/14 or anyimplant in general can include preformed apertures to accommodate thefixation material, i.e., sutures, screws, staples, darts, or clips.Fixation to tissue enhances the fixation function of the implantedstructure.

The tissue to which a given implant is fixed can include soft tissue,such as mucosa, submucosa, fascia, or muscle in the pharyngeal walls,the base of the tongue; the vallecula; the soft palate with uvula; thepalatine tonsils with associated pillar tissue, and the epiglottis.

The tissue can also include bone within the pharyngeal conduit, e.g., ahyoid bone or a vertebra.

Various systems for mechanically securing implanted magnetic structuresin tissue, muscle, or bone are shown in U.S. patent application Ser. No.10/718,254, filed Nov. 20, 2003 and entitled “Devices, Systems, andMethods to Fixate Tissue Within the Regions of the Body, Such as thePharyngeal Conduit,” which is incorporated herein by reference.

A given magnetic structure or implant can implanted in either ahorizontal or vertical anatomic orientation, and/or in a linear orcurvilinear pattern within the pharyngeal conduit or elsewhere in thebody.

B. Fixation in Muscle or Other Soft Tissue

-   -   1. Direct Approach (The Flap)

Implants can be placed directly within the mucosa, or the submucosa, oragainst the fascia, or against or within muscle within the pharyngealwall and/or tongue (the locations shown in FIG. 2) or elsewhere in thebody by raising a surgical flap.

Using a flap approach, no sutures need to be placed through the mucosainto the implant. It has been discovered that placement of suturesthrough the mucosa can provide a conduit effect along the suture linefrom the contaminated oral cavity into the sterile implant pocket. Also,when using a flap approach, the implant can be better stabilized underdirect vision, so the implant can be better positioned, sincevisualization is direct.

The flap approach can be accomplished in a single stage or in twostages. Either approach can be used to place a magnetic structure or anyother type or style of implant in the pharyngeal conduit or elsewhere inthe body.

-   -   a. Single Stage Flap Approach

FIGS. 19A to 19D show the use of a single stage flap approach to placean implant in a lateral pharyngeal wall. FIGS. 20A to 20D show the useof single stage flap approach to place an implant in a posterior-lateralpharyngeal wall. FIGS. 21A to 21D show the use of a single stage flapapproach to place an implant in a posterior region of a tongue.

After transoral exposure of the oral cavity, lateral wall or tongue, aflap 70 is formed in the tissue plane (see FIGS. 19A, 20A, and 21A). Theflap 70 is formed by using an appropriate surgical cutting instrument toform an incision having a desired shape. The formed flap 70 can be ofvarious shapes and positions depending on the desired location, shapeand proposed function of the implant. As examples, bilateral pharyngealwall flaps 70 can be configured in a curvilinear upside down “L” shapefor placement of directly opposite implants. A superior or inferiorbased “U” shaped flap can be configured along the posterior andposterior-lateral pharyngeal walls for placement of twoposterior-lateral implants either connected or not across the midline.Tongue flaps of similar configurations can likewise be elevated.

Elevating a flap 70 can expose underlying muscle 72 (see FIGS. 19B, 20B,and 21C), which can be fascial covered. Excellent exposure is affordedfor controlled placement of the implants. The pharyngeal flaps (bothlateral and posterior-lateral) can expose pharyngeal constrictormuscles, and the tongue flap can expose genioglossal muscle,

As FIGS. 19C, 20C, and 21C shows, a selected implant 74 is thenstabilized within the mucosa, or the submucosa, or against the fascia oragainst or within muscle 72 in each elevated flap 70, e.g., with simplesutures 76, and/or mattress sutures, and/or staples, and/or clips,and/or darts, and/or hooks or fasteners attached to or formed on thebiocompatible body of the structure (which can be biodegradable, ifdesired). The implant 74 is desirably dipped or impregnated with anantibiotic. In the case of the posterior-lateral flap (see FIG. 20C),bone anchors 78 placed into the anterior vertebral column can be used.

It should be appreciated that, instead of forming a flap, a surgicalpocket can be formed to receive the implant. The pocket is formed bydilating tissue by use of a trocar or expandable dissector, to open atissue space to receive an implant. Using a pocket approach, like theflap approach, no sutures need to be placed through the mucosa into theimplant. The implantation and implant fixation techniques describedherein with regard a surgical flap apply to surgical pockets as well.

As FIGS. 19D, 20D, and 21D show, with the implant 74 now stabilized adistance away from the flap incision, the flaps 70 (or pocket) can beclosed, e.g., with one or more absorbable or non-absorbable sutures 80,adhesives, or glues such as cyanoacrylate, or cements such as polymethylmethacrylate (PMMA) cement. An absorbable sutures 80 can be rapidlydissolving (e.g., seven days), or comprise a longer lasting absorbablysuture such as Vicryl™ material, Supplemental systemic antibiotics aredesirably utilized, which can be delivered into the flap 70 (or pocket)before or after implant placement.

Agents to stimulate rapid fibrosis can be used for furtherstabilization. Examples of such agents include fibrin sealants, tissuesealants, talc (dry or slurry), doxycycline, bleornycin, povidoneiodine, minocycline, doxorubicin, streptokinase, urokinase, sodiumtetradecyl sulfate, and/or silver nitrate. Other coatings to promote thestability of the implant 74 include calcium hydroxylapatite, aluminumoxide, bioactive hydroxyl apatite, or tricalcium phosphate. Such agentscan be applied only at pre-selected locations on the implant 74, e.g.,such as bottom and side boundaries, to leave easy access to the topportion of the implant 74 for removal. Alternatively, such agents can beinjected directly into the flap 70 (or pocket), or may used to irrigatethe flap 70 (or pocket), or may be placed within a gel or hydrogel inthe flap 70 (or pocket).

Tissue adhesives, fibrin sealants, and glues such as cyanoacrylate, orcements such as polymethyl methacrylate (PMMA) cement can be applied toeither improve stabilization or replace mechanical sutures or fasteners.A tissue ablation agent or energy source may be used to form avascularpockets.

Tissue ingrowth materials can also be used, as will be described ingreater detail later.

-   -   b. Two Stage Flap Approach

The techniques described above can also be done in a two stage manner.

In this arrangement (see FIG. 23A), pharyngeal flaps 70 (either lateralor posterior-lateral) and/or a tongue flap 70 can be formed in themanner just described, which can expose pharyngeal constrictor muscles72 or genioglossal muscle 72, which can be fascial covered. FIG. 23Ashows, for purpose of illustration, the flap being formed in a lateralpharyngeal wall. Alternatively, a surgical pocket can be formed.

A modular receptacle 82 or sleeve (see FIG. 22) is then stabilized,e.g., within the mucosa, or against the fascia, or against or withinmuscle, in each flap 70 (see FIG. 23B) (or pocket), with resorbable ornon-resorbable sutures, and/or staples, and/or hooks and/or fasteners,and/or darts, and/or clips, and/or screws, and/or adhesives, and/orglues such as cyanoacrylate, or cements such as polymethyl methacrylate(PMMA) cement. The flaps 70 (or pocket) are then closed withnon-absorbable or absorbable suture 80, adhesives, or glues such ascyanoacrylate, or cements such as polymethyl methacrylate (PMMA) cement.Supplemental systemic antibiotics are desirably utilized.

As FIG. 23C shows, the implanted receptacle 82 is allowed to stabilizewithin the flap or pocket by fibrous capsule formation or tissueingrowth. To accelerate or enhance stabilization of the receptacle 82 inthe flap 70 or pocket, as in the single stage approach, agents can beused to stimulate rapid fibrosis in tissue surfaces, and/or tissuesealants, adhesives, and/or glues can be applied to either improvestabilization or replace mechanical sutures or fasteners; and/or tissueablation agents or energy sources can be applied to form avascularpockets, and/or tissue ingrowth materials can be used, as will bedescribed in greater detail later.

After the receptacle 82 has been allowed to stabilize within the flap 70(or pocket), a selected implant 74 is loaded into the receptacle 82 (seeFIG. 23D). This can be done, e.g., by re-opening a portion of the flapor pocket, or the use of transmucosal trochars.

The two stage approach allows stabilization of a basic implant support(i.e., the receptacle 82) to occur within a flap or pocket prior to theintroduction of the operative implant 74, e.g., one subject to magneticforces or another potentially destabilizing force. The two stageapproach also allows one to titrate, e.g., magnetic force requirementsto the individual patient's needs without replacing the basic implantsupport.

C. Instrument Approaches

Implants of the types described herein, or of other designs andfunctions, can also be placed percutaneously into the pharyngeal walland/or tongue (the locations shown in FIG. 2) or elsewhere in the bodyby use of percutaneous instrument systems 84, without opening a flap oranother incision site. An instrument system 84 may be variouslyconstructed.

FIGS. 24A to 24C show a representative system 84. The system 84 includesan access cannula 86 which, in use, can be deployed within the oralcavity to create a percutaneous path to a selected implantation siteeither in a tongue (see FIG. 26A) or in a pharyngeal wall (see FIG.26B). A trocar-tip guide wire 90 can be used to initially puncture thetargeted tissue site. A cannulated tissue plane dissector 88 can then bepassed over the guide wire 90 to create an entry site to the tissue andto separate the tissue layers at the implantation site. The guide wire90 can then be removed, and the access cannula 86 can be passed over thedissector 88 to the implantation site. The dissector 88 and guide wire90 are removed, to open a working channel through the access cannula 86to the implantation site.

Alternatively, the dissector 88 and access cannula 86 can be deployednested together, being passed as a unit into tissue, with or without useof a guide wire. The blunt tip of the dissector 88 projects beyond thedistal end of the cannula 86, serving to open an entry site and separatethe tissue layers at the implantation site. The dissector 88 can then beremoved from the cannula 86, to open the working channel.

In either embodiment, another instrument may be deployed through theworking channel of the cannula 86, if necessary, to create a surgicalpocket in the tissues to receive the implant.

As FIG. 24B shows, the system 84 may include a implant delivery tool 92.The tool 92 carries an implant 94 in a preloaded condition within itsdistal end. The tool 92 is passed through the working channel of thecannula 86 to the implantation site. A plunger 96, or rod, abuts againstthe implant. By holding the plunger 96 stationary and pulling back uponthe tool 92, the implant can be expelled from distal end of the tool 92into the prepared implantation site (see FIG. 24C). The cannula 86 andthe implant delivery tool 92 can, at the appropriate time, be removed asa unit, leaving the implant behind.

Alternatively, the implant 94 can be loaded directly into the proximalend of the cannula 86, and the plunger 96 passed through the cannula 86to advance the implant to the distal tip of the cannula 86. Holding theplunger stationary and pulling back on the cannula 86 expels the implantinto the prepared implantation site. The cannula 86 and plunger 96 canthen removed as a unit, leaving the implant behind.

As FIG. 24C shows, a given implant 94 may be rolled or folded within theworking channel of the cannula 86 or within the delivery tool 92 duringdeployment. In this arrangement, the implant 94 can include a materialthat actively or passively reshapes the implant 94 into its in-usecondition after deployment into the implantation site. For example, thematerial may urge the implant 94 toward a lay-flat or curvilinear in-usecondition when free of the cannula 86. For example, the material maypossess a spring constant or include a shape memory to self-expand tothe desired lay-flat or curvilinear in-use condition. Alternative, theimplant 94 may be deployed in conjunction with a shaping member thatactively reshapes the implant 94 into it in-use condition afterdeployment from the cannula 86. For example, the implant 94 may bewrapped around an expandable structure that expands or inflates to forcethe implant to flatten. Alternatively, the implant 94 may be wrappedaround a mechanically expanding member that transforms linear orrotational motion into motion that will lay out the implant 94.

In FIGS. 24A to 24C, the cannula 86 is shown to be cylindrical in shape,and the other tools that pass through the working channel arecorrespondingly shaped. The shape can be cylindrical, oval, rectilinear,or other configurations. As FIGS. 25A and 25B show, the shape of thedelivery tools may be customized to shape of the implant 94 itself. Forexample, when the implant 94 comprises a rectilinear shape, the workingchannel itself can be correspondingly rectilinear in cross section, asFIGS. 25A to 25C show.

For example, in this arrangement (see FIG. 25A), the rectangular cannula86 and the rectangular dissector 88 form a combination tool 98, whichcan be manipulated to gain access to the tissues. The tool 98 nests thedissector 98 within the cannula 86. The dissector 98 takes the form of asharp, inner stylet with a trocar or blade tip that can puncture thetissue. The cannula 86 takes the form of an outer stylus holding thedissector 98. The combination tool 98 punctures the tissue, after whichthe dissector 88 is withdrawn from the cannula 86. If it is necessary toform a pocket within the tissue, another blunt tip instrument may bepassed through the working channel of the cannula 86 to further separatethe tissue layers.

As shown in FIG. 25B, a rectangular implant 94 is loaded into arectangular delivery tool 92. The delivery tool 92 is passed through theworking channel of the cannula 86 to the site that has been prepared forimplantation. A rectangular plunger 96 is advanced through the deliverytool 92 to expel the implant 94 from the tool 92 into the implantationsite.

Once deployed, the implant 94 may or may not be further anchored to theunderlying tissues/muscle layer. Within the implantation site, theposition of the implant 94 may be stabilized using a suitablestabilization element, e.g., one or more staples, and/or clips, and/ordarts, and/or sutures, and/or medical adhesives or glues, as previouslydescribed. Stabilization can be achieved without fixation of the implantto mucosa or submucosa tissue, if desired. Tools that place thestabilizing element in the implant 94 may be an integrated part of theaccess cannula or implant delivery tool, or may comprise one or moreseparate tools that are themselves deployed through the working channelof the cannula 86, or may comprise one or more tools that are deployedby some other means.

The working channel of the cannula 86 can also be used to flush thedelivery site with antibiotic solutions prior to, during, and afterimplant delivery. The antibiotic solutions can include, e.g.,chlorohexalin, kanamicin, Baytril, cephalexin, or gentamicin.

The cannula and other tools of the system can be made of metal, plastic,or ceramic materials, or combinations thereof. The cannula and othertools can be made of flexible materials, allowing the instruments to beflexed or shaped during use (as FIG. 26B shows for purposes ofillustration).

As shown in FIG. 30A, the implant 94 can carry integrated stabilizationelements 100 that automatically anchor the implant to tissue when it isreleased into the implantation site. Stabilization elements 100 can beintegrated to the implant in various ways. For example, as shown in FIG.30A, the tissue stabilization elements 100 are carried at the end ofelastic arms 102 and 104, having spring-like characteristics. Theelastic arms 102 and 104 are secured at opposite ends of the implant 94,and they occupy different planes. The elastic arms 102 are secured alongthe front surface of the implant 94, and the elastic arms 104 aresecured along the rear surface of the implant 94. This arrangementbalances the stabilizing forces about the implant 94, as well asfacilitates the deployment of the elements 100 in the first instance.The elastic arms 102 and 104 may be made of shape memory plastic ormetallic materials that expand within the plane of the implant 94 oroutside the plane of the implant 94.

The elastic arms 102 and 104 are placed into compression and bent inwardtoward the implant 94, into what can be called an inboard condition,when the implant 24 is confined within the delivery tool 92 (see FIG.30C). When free of the confines of the delivery tool 92 (see FIGS. 30Aand 30D), the arms 102 and 104 spring outward from the implant 94, dueto their spring-like characteristics, into what can be called anoutboard condition, engaging tissue.

In this arrangement (see FIG. 30B), the distal end of the delivery tool92 includes opposing slots 106 that align with the elastic arms 102 onthe trailing edge of the implant 94 (i.e., the edge that is last to exitthe tool 92 during implant deployment). The elastic arms 104 on theleading edge of the implant 94 (i.e., the edge that is first to exit thetool 92 during implant deployment) do not align with the slots 106.

The implant 92 is loaded into the tool 92, trailing edge first, with theelastic arms 102 and 104 in their outboard condition. The slots 106accommodate passage of the elastic arms 102 on the trailing edge of theimplant 92, as the implant is progressively loaded into the tool 92. AsFIG. 30B best shows, the elastic arms 102 on the trailing edge of theimplant 92 will abut the terminus 108 of the slots 104 about the sametime that as the elastic arms 104 on the leading edge of the implant 92abut the distal terminus 110 of the tool 92. Loading the implant 92further into the tool 92 results in resiliently bending the elastic arms102 and 104 progressively forward into their inboard condition. The slotterminus 108 will deflect the elastic arms 102 forward into compression,and the end terminus 110 will deflect the elastic arms 104 forward intocompression. When fully loaded within the tool 92, the walls of the tool92 keep the elastic arms 102 and 104 in compression in their inboardcondition.

At time of deployment, the plunger 96 is held stationary, and the tool92 is drawn away from the implantation site. This will release theimplant 92 from the confines of the tool 92, leading edge first. As theleading edge of the implant clears the tool 92, the arms 104 will springoutward to their outboard condition (see FIG. 30D). As the trailing edgeof the implant clears the tool 92 (as FIG. 30A shows), the arms 102 willspring outward to their outboard condition. The self-deployedstabilization elements 100 anchor the implant 94 in adjacent tissue,without need for deployment of a separate stabilization tool.

Other systems and devices may be used to deliver an implant to animplantation site in the pharyngeal conduit or elsewhere in the body.For example, FIGS. 27A and 27B show a hand-held tool 112 comprising adelivery cannula 114 coupled by a flexible tubing 116 to a handle 118.An implant 94 is carried within the cannula 114. The cannula 114includes a needle-like, tissue penetrating distal tip 122. The distaltip 122 can be placed into tissue in the tongue or pharyngeal wall,while the handle 118 remains fully or partially inside the oral cavity.

A plunger 118 abuts against the trailing edge of the implant 94. Theplunger 118 is coupled by a push-pull cable (which passes through thetubing 116) to an actuator 120 on the handle 114. Pushing forward on theactuator 120 advances the plunger 118 (see FIG. 27B), which expels theimplant from the cannula 114 into the implantation site.

In the alternative embodiment shown in FIGS. 28A and 28B, the actuator120 takes the form of a trigger mechanism 124, which can be actuated bysqueezing a slidable aft trigger member 126 toward a stationary forwardhandle 128, or by pulling a pivot trigger 130 (shown in phantom lines)toward the handle 128. In the alternative embodiment shown in FIGS. 29Aand 29B, the actuator 120 takes the form of a sliding thumb lever 132.

D. Tissue In-Growth Surfaces

In addition to any of the just-described tissue fixation methodologies,a given implant can include a tissue in-growth surface 70 (see FIG. 2).The use of such surfaces 70 has previously been described in associationwith the polymer-bonded, hybrid, and layered magnetic structures.

In general, the surface 70 provides an environment that encourages thein-growth of neighboring tissue on the implanted structure. Tissuein-growth is defined as the filing of pores in an implanted materialwith cellular material. As in-growth occurs, the implanted structure 12will become securely anchored, resisting migration or extrusion from thetissue. The tissue in-growth surface 70 thus enhances tissue adhesionand stabilization, and thereby further stabilizes and fixes the positionof the implanted structure 12 in the targeted implantation site.

The tissue in-growth surface 70 can be formed in various ways, such asthe porous nature of the material, knitting, weaving, through holes, ormolding a porous structure or surface. Examples of suitable materialsinclude polytetrafluoroethylene (PTFE), expanded PTFE, polyethyleneterephthalate such as Dacron® (PET) fabric, other permanent polyesters,polyurethane, silicone, polypropylenepolyvinyl alcohol, biodegradablepolyesters such as polylactic acid and polyglycolic acid.

It may be desirable to mechanically anchor the implanted magneticstructures while allowing in-growth to occur. Anchoring may beaccomplished by use of resorbable or non-resorbable sutures, screws orother mechanical fasteners made of resorbable or non-resorbablematerials such as polyglycolic acid or other similar compounds. Tissueadhesives and/or tissue cements such as PMMA and/or tissue sealants,and/or tissue glue such as cyanacrylate may also be used to providetissue adhesion, fixation, and stabilization.

Complete tissue in-growth is determined by the percentage of thematerial that has been infiltrated by the cellular material. With poresizes from 100 micrometers to 500 micrometers, blood vessels can beformed. With pore sizes of 10 micrometers to 100 micrometers, cells tosmall capillaries can form.

Also, materials or shapes may be used that encourage tissue or fibroticencapsulation of the implant 94, with or without tissue ingrowth.

III. Systems for Providing Treatment

It is apparent from the foregoing that various systems can be created,based upon the above-described implant structures, implantation devices,and surgical implantation techniques, to make it possible for healthcareproviders to treat physiologic conditions with enhanced effectiveness.

For example, as shown in FIG. 31, one can make available a system 200that can provide treatment for dysfunctions affecting the pharyngealconduit, such as sleep disordered breathing, snoring, or sleep apnea. Inone desired embodiment, the system 200 would have an implant component202 and an implantation component 204.

The implant component 202 can include providing one or more implants 206that are sized and configured to be implanted in a targeted tissueregion comprising at least one pharyngeal structure or at least oneanatomic component within a pharyngeal conduit. Several embodiments ofimplants 206 having this characteristic have been described herein.Other representative embodiments are described in U.S. patentapplication Ser. No. 10/718,254, filed Nov. 20, 2003 and entitled“Devices, Systems, and Methods to Fixate Tissue Within the Regions ofthe Body, Such as the Pharyngeal Conduit”; U.S. patent application Ser.No. 10/656,861, filed Sep. 6, 2003 and entitled “Magnetic Force Devices,Systems, and Methods for Resisting Tissue Collapse within the PharyngealConduit”; U.S. patent application Ser. No. 10/236,455, filed Sep. 6,2002 and entitled “Systems and Methods for Moving and/or RestrainingTissue in the Upper Respiratory System”; and U.S. Provisional PatentApplication Ser. No. 60/441,639, filed Jan. 22, 2003 and entitled“Magnetic Splint Device and Method for the Treatment of Upper AirwayCollapse in Obstructive Sleep Apnea;” and U.S. Provisional PatentApplication Ser. No. 60/456,164, filed Mar. 20, 2003 and entitled“Device and Method for Treatment of Sleep Related Breathing DisordersIncluding Snoring and Sleep Apnea,” which have been incorporated hereinby reference.

The system 200 desirably includes an implantation component 204, becauseof challenges that are presented in the placement of implants 206 in thedynamic tissue environment of the pharyngeal conduit. The implantationcomponent 204 includes providing at least one tool 208 and/orinstructions 210 for placing the implant 206 in a tissue region, e.g.,through a percutaneous access path, using the tools described herein andshown in FIGS. 24 to 30; or by forming a surgical flap as describedherein and shown in FIGS. 19 to 23; or by forming a surgical pocket, asalso described herein.

The implantation component 204 can also include providing at least onetool 212 and/or instructions 214 for stabilizing the implant within amucosa, or a submucosa, or against a fascia, or against or within amuscle, as described herein. Alternatively, the tool 212 and/orinstructions 214 can make possible the stabilization of the implantagainst submucosa, or a fascia, or against or within a muscle, withoutstabilizing through a mucosa, as described herein. Other tools andinstructions can be provided, e.g., to make various mechanical fixationmaterials (as described herein) accessible; or to make agents thatstimulate rapid fibrosis (as described herein) available; or to provideantibiotic materials (as described herein).

The basic components 202 and 204 of the system 200 can be providedindividually, or packaged in the form of a kit 216, as FIG. 31 shows.The various instructions can be in written form, electronic form, orverbal form, which can be provided in the kit 216 and/or as part of atraining program or web site for clinicians.

The above-described embodiments of this invention are merely descriptiveof its principles and are not to be limited. The scope of this inventioninstead shall be determined from the scope of the following claims,including their equivalents.

1. An implant comprising a biocompatible flexible polymer matrix, and aplurality of magnetic particles bound within the biocompatible flexiblepolymer matrix in a desired ratio of magnetic particles to abiocompatible polymer and being magnetized to possess a desiredpolarity, the desired ratio providing flexure of the polymer matrixbetween the magnetic particles, the biocompatible flexible polymermatrix being sized and configured for implanting in a tissue regionalong a pharyngeal conduit to magnetically interact with a source ofmagnetic force.
 2. An implant according to claim 1, wherein the magneticparticles comprise isotropic or anisotropic materials.
 3. An implantaccording to claim 1, wherein the magnetic particles comprise a materialselected from the group of NdFeB, SmCo, ferrite, and alnico.
 4. Animplant according to claim 1, wherein the biocompatible polymer includesa material selected from the group of polycarbonate, silicone rubber,polyurethane, silicon elastomer, flexible plastic, and semi-flexibleplastic.
 5. An implant according to claim 1, wherein the biocompatibleflexible polymer matrix includes a tissue in-growth region.
 6. Animplant according to claim 1, wherein the desired ratio forms regions ofdifferent magnetic particle densities within the biocompatible flexiblepolymer matrix.
 7. An implant according to claim 1, wherein the desiredratio forms an essentially uniform magnetic particle density within thebiocompatible flexible polymer matrix.
 8. An implant according to claim1, further including at least one discrete permanent magnet encapsulatedwithin the biocompatible flexible polymer matrix with the magneticparticles, the biocompatible flexible polymer matrix allowing flexureamong the magnetic particles and the at least one discrete permanentmagnet.
 9. An implant according to claim 8, wherein the permanent magnetand the magnetic particles are magnetized to have a common polarity. 10.An implant according to claim 1, further including at least onepolymer-bonded magnet encapsulated within the biocompatible flexiblepolymer matrix with the magnetic particles, the biocompatible flexiblepolymer matrix allowing flexure among the magnetic particles and the atleast one polymer-bounded magnet.
 11. An implant according to claim 10,wherein the polymer-bonded magnet and the magnetic particles aremagnetized to have a common polarity.
 12. An implant according to claim1, further including a flux shield comprising a soft ferromagneticmaterial coupled to the biocompatible flexible polymer matrix.
 13. Animplant according to claim 1, wherein the desired polarity establishes adesired magnetic pole, and further including at least one stabilizationmagnet coupled to the biocompatible flexible polymer matrix, thestabilization magnet including a magnetic pole that is the same as thedesired magnetic pole and that is oriented normal or at an acute angleto the desired magnetic pole.
 14. An implant according to claim 1wherein the biocompatible flexible polymer matrix is sized andconfigured for implantation in one of a pharyngeal wall; a tongue; avallecula; a soft palate; a uvula; a palatine tonsil; and an epiglottis.15. An implant according to claim 1 wherein the desired polarityestablishes a desired magnetic pole.
 16. A magnetic force systemcomprising an implant comprising a biocompatible flexible polymermatrix, and a plurality of magnetic particles bound within thebiocompatible flexible polymer matrix in a desired ratio of magneticparticles to a biocompatible polymer and being magnetized to possess adesired polarity, the desired ratio providing flexure of the polymermatrix between the magnetic particles, the biocompatible flexiblepolymer matrix being sized and configured for implanting in a tissueregion along a pharyngeal conduit to magnetically interact with a sourceof magnetic force, and a source of magnetic force sized and configuredfor placement to magnetically interact with the implant to resistcollapse of the tissue region.
 17. A system according to claim 16wherein the biocompatible flexible polymer matrix is sized andconfigured for implantation in one of a pharyngeal wall; a tongue; avallecula; a soft palate; a uvula; a palatine tonsil; and an epiglottis.18. A system according to claim 16 wherein the desired polarityestablishes a desired magnetic pole that magnetically interacts with thesource of magnetic force.